Helsinki Upper Secondary School of Natural Sciences to feature more than 1,700 cubic metres of wood

A new wooden general upper secondary school with an emphasis on natural sciences will be completed in connection with the Kumpula campus of the University of Helsinki. For SRV, the project represents lifecycle-wise construction, supported by wood construction experts from Sweco all the way from the call for tenders to implementation planning.

The new Helsinki Upper Secondary School of Natural Sciences is owned by Helsinki University Properties Ltd. The new building and shared use facilities of the school will be opened to approximately 900 general upper secondary students in autumn 2023. The Kumpula campus is also home to the University of Helsinki, meaning that the general upper secondary students will have early access to the world of science. The general upper secondary school may also utilise the teaching and sports facilities of the university.

SRV implemented the project as a collaborative project management contract, with a design team consisting of experienced wood construction professionals right from the start of the tendering process. “Due to the COVID-19 pandemic, we were unable to meet face to face for a long time, but working together came naturally to us from the start,” says Design Unit Director Robert Holmström from SRV Construction Ltd.

The design team remained unchanged from start to finish. “It was fantastic to be able to implement structural design all the way from the tendering and development stages to implementation planning,” says Project Manager Susanna Friman from Sweco.

The wooden general upper secondary school strengthens SRV’s already extensive expertise in wood construction. “We want to create lifecycle-wise buildings that take the client’s wishes, financial aspects, users’ wellbeing and the environment into account in the long term,” Holmström says.

The spaces can withstand almost anything

The client and the future staff and users of the school were heavily involved in the process throughout planning. Their key wishes included the adaptability of the spaces, which was ensured by implementing the frame as a combination of a pillar and beam solution and solid wood CLT elements.

“Load-bearing partition walls were only implemented in stairways. Otherwise, the spaces are equipped with flexible movable folding walls,” says Senior Structural Engineer Petri Kokkonen from Sweco. CLT-concrete composite slabs were used in the intermediate floors. “All in all, more than 1,700 cubic metres of CLT and glued laminated timber were utilised in the school.”

The adaptability of the spaces was also taken into account by implementing a larger than usual superimposed load. “Usually, a sufficient superimposed load for teaching facilities is 2.5 kilonewtons per square metre, but for this site the superimposed load is 5 kilonewtons,” Kokkonen says. To put this into perspective, the superimposed load for ventilation machine rooms is usually approximately 4 kilonewtons. “The structural strength is at a level where the general upper secondary school facilities should be able to withstand almost any kind of use.”

Joint commitment to schedules

The entire project group was committed to shared risk management from the start, and the factors monitored included humidity control, budget and schedule, to name a few. Each party recorded their own schedules in a pilot tool developed by SRV. “Commitment to shared schedules truly comes into its own when the entire design team drafts the schedules together,” Holmström says.

Cooperation was especially important in the fire protection design for the building. The site is compliant with the requirements of fire resistance class P0. “In order to meet the requirements, the project applied solutions that differed from dimensioning tables, which required close cooperation with rescue authorities and building control,” Friman says.

The finished wooden general upper secondary school will feature many impressive details, such as a diagonally timbered facade and a massive outdoor canopy serving as the focal point. “Connecting its load-bearing pillars and beams to the grid structure of the roof was one of the most interesting tasks of the project,” Kokkonen says. “The pillars that are more than 20 metres long and the 30-metre beam had some of the largest dimensions of any glued laminated timber structures we have designed.”

Picture: Arkkitehdit AFKS, SRV